Formed in 1962, the Group aims to challenge, re-define and develop standards of care in all controversial areas of breast cancer diagnosis and therapy, including rare conditions such as male breast cancer. The Group researches long-term outcomes and follows all patients throughout their lives.


Breast cancer is the most commonly diagnosed cancer in women and the most common cause of cancer death in women worldwide (1 in 6 cancer deaths)1. According to WHO, in 2020, there were 2.3 million women diagnosed with breast cancer 2. Incidence rates vary across countries. In a developed country setting, about 1 in 8 women will be diagnosed with breast cancer in their lifetime [1].

Early-stage breast cancer is defined as disease confined in the breast (lump of size up to 5cm) and / or regional lymph nodes, without distant metastases (spread of cancer to other organs). With treatment, women with early breast cancer have a very good prognosis (chance of survival). The primary treatment (core treatment) for early breast cancer is surgery. Reducing the chances of recurrence and therefore increasing the survival rate of these patients, means additional treatment (chemotherapy and /or radiotherapy) after surgery. These additional treatments bear toxicities for the human body and researchers aim to find ways of reducing/limiting these adverse effects and thus increasing their quality of life, without affecting their chances of survival. The following three EORTC Breast Cancer Group clinical trials are examples of reducing treatment without compromising patients’ survival rates (very good prognosis) but having a significant increase in their quality of life.

Studies over the years have shown that treating women diagnosed with early breast cancer with chemotherapy after surgery, has significant results in their overall survival. Chemotherapy however can negatively affect patients’ overall health and quality of life in the long term. The EORTC MINDACT study sought to investigate whether women diagnosed with early breast cancer that hasn’t spread beyond the breast and/or the nearby lymph nodes (masses of tissue that help the body to fight disease), could be spared chemotherapy treatment after surgery, without affecting their overall survival rate.  

This led to the development of a test, called MammaPrint® which examines the profile of 70 different genes and determines which patients bear genomic low risk and can therefore avoid chemotherapy.  This was the first effective tool of its kind in assessing the prognosis of these patients.  

The study found that 94.7% of women who were identified as genomic low risk using the 70 gene signature test, and therefore did not receive chemotherapy, were free of disease 5 years later.  

Long-term monitoring of these patients at 8.7 years confirmed the initial trial results and found that 95.1% were free of disease and free of metastasis (disease spread) after 5 years. The EORTC MINDACT trial has proven instrumental in reducing treatment where possible and paving the way towards optimised care and quality of life for patients.

Study coordinator: Prof. Fatima Cardoso

This EORTC clinical trial was part of a series of trials that proved that breast conserving treatment can be used in certain women diagnosed with early breast cancer instead of mastectomy (removal of the breast). It proved that patient survival was identical between the two treatment options. This is an important EORTC study, as it enabled to change the standard of practice by improving the patients’ quality of life while equally helping doctors to better inform their patients of their options. To date, for most women diagnosed with early breast cancer, breast conservation treatment remains an option sparing them from medically unnecessary more extensive surgery (removal of the breast). 

In women diagnosed with early breast cancer, the first step before deciding on a treatment is for doctors to assess whether the tumour has affected the lymph nodes (masses of tissue, part of the body’s immune system, that help the body to fight disease). This procedure is called sentinel node biopsy. Most cases are negative, however, in the case of a positive biopsy, the lymph nodes are removed (called axillary dissection). This nonetheless negatively impacts the quality of life of patients as removal of the lymph nodes close to the breast is associated with lifetime health complications (swelling of arm, pain etc) in the majority of cases. The AMAROS study, sought to investigate whether in cases of a positive sentinel biopsy, radiation of the affected area could be an alternative to surgical removal and thus sparing women from permanent health complications following the surgical removal of the lymph nodes. The study found radiation to be an effective alternative to surgical removal in regional control of the tumour.

Study coordinator: Prof. Emiel Rutgers


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